\section{试验装置设计}\label{experitment}
%To verify the accuracy of the proposed parallelized TLM iteration method, we assembled five actuator samples and performed the testing experiments. As shown in Fig. \ref{equip}, it is an Automatic Plug Test Machine, which can measure the force in the range from 0 N to 500 N and has the ability to move at the least speed of 0.01 mm/min. In Fig. \ref{detail}, the actuator is fixed in the work station, and its movable part is connected with the force sensor. In the experiment, the work station is moved slowly, so that we can obtain the magnetic force at different displacements. The range of movement is about 2.4 mm and the magnetic force is recorded every 0.1 mm. In addition, the experiment is performed on the three conditions in Table \ref{tab1}. We also tested the B-H characteristic of iron core which is shown in Table \ref{tabbh}.  The coercivity $H_c$ of NdFeB is 883310 A/m and its remanence $B_r$ is 1.21 T.
为了验证所提出的并行TLM方法的正确性，我们组装了五个接触器的样品，并完成了相关的试验测量。如图 \ref{equip}所示，这是一个自动插拔力测试仪，它可以测量 0 N到 500 N的力，最小的移动速度为 0.01 mm/min。在图 \ref{detail} 当中，接触器固定被固定在工作台上，接触器的衔铁与力传感器相连。在试验当中，工作台缓慢朝一个方向移动，我们可以获得衔铁在不同位置的电磁力大小。衔铁的运动行程大约为 2.4 mm，试验当中，每运动 0.1 mm记录一次电磁力数据。除此之外，试验按照表 \ref{tab1} 中的三种条件进行。对于接触器当中的铁芯材料，它的典型B-H数据如表 \ref{tabbh}所示。永磁NdFeB的矫顽力$H_c$大小为 883310 A/m，剩磁$B_r$ 为 1.21 T。
\begin{figure*}[tb]
        \subfigure[完整的试验系统]{
            \label{equip} %% label for second subfigure
            \includegraphics[width=5cm]{equip}}
        \hspace{3mm}
        \subfigure[详细的测试结构]{
            \label{detail} %% label for first subfigure
            \includegraphics[width=3cm]{detail}}
    \caption{试验装置搭建
     (1-力传感器. 2-连接器. 3-测试样品. 4-夹具.)}
    \label{teste} %% label for entire figure
\end{figure*}
\begin{table*}[h]
\caption{三种不同条件}\label{tab1}
{\begin{tabular*}{20pc}{@{\extracolsep{\fill}}lll@{}}\toprule
序号 & 上线圈电压 & 下线圈电压 \\

1 & $0\,V$ & $0\,V$ \\
2 & $28\,V$ & $0\,V$ \\
3 & $0\,V$ & $28\,V$ \\
\bottomrule
\end{tabular*}}{}
\end{table*}
\begin{table*}[h]
\caption{铁芯 (材料: DT4E)的典型B-H数据}\label{tabbh}
{\begin{tabular*}{20pc}{@{\extracolsep{\fill}}lll@{}}\toprule
序号 & H/(A/m) & B/(T) \\

1 & 0 & 0 \\
2 & 200 & 1.2 \\
3 & 300 & 1.3 \\
4 & 500 & 1.4 \\
5 & 1000 & 1.5 \\
6 & 2500 & 1.62 \\
7 & 5000 & 1.71 \\
8 & 15000 & 1.851 \\
\bottomrule
\end{tabular*}}{}
\end{table*}


